File Sync problem

Hi all,
I'm working on a file sync app and what I want to be able to do is update the destination folder when any file is changed in the source folder. I tried using the FileTime() to compare the file dates . The problem is however that when I use copyfile() the new file always has the current time and not the time of the original. So subsequent compare will always flag the original file as a recent update even though it was just updated.
Is there a better way to tackle this problem?

Thanks for all the help.

Don't use exact match, use "if source file time is BIGGER then sync"

Pseudo code:

SourceFile time = 1001
DestinationFile time = 900

Compare times:
- since sourceFile time (1001) IS BIGGER DestinationFile time (900)
=> make a copyfile, now times are:

SourceFile time (1001)
DestinationFile time (2009)

Compare times:
- since sourceFile time (1001) IS NOT BIGGER than DestinationFile time (2009)
=> do nothing

if you have folder A(source) and folder B(dest) and you never want to copy/sync changes from B to A, then you could possibly just use hashing.

hash a file in A and if that hash is different from the same file in B then you can 'assume' a change has happened in A (again assuming you aren't updating files in B separately).

example code to hash files can be found here

that's just another way of approaching it :).

Thanks a lot guys. That solves my problem.